This project focuses on the human Y chromosome in the context of the Human Genome Initiative. The principal long-term goal of this project is complete definition of the genetic content of the human Y chromosome. Toward that end, a detailed genetic deletion map of the chromosome will be constructed, overlapping recombinant DNA clones spanning the chromosome will be isolated, and the nucleotide sequence of the chromosome will be determined. During the early course of this work, high priority will be given to the development of efficient DNA sequencing strategies using automated instruments. The resulting information will provide a framework for elucidating the function of the Y chromosomes in processes as diverse as spermatogenesis, tumorigenesis, and embryonic somatic and sexual development. These studies will also reveal much about the complex functional, structural, and evolutionary relationship between the human X and Y chromosomes.